1. Field of the Invention
The present invention relates to a compound filled in lead integrated circuit package product, and more particularly to a substrate made of metal and filled in with compound or encapsulation material to support the lead of the packaged IC product.
2. Description of Related Art
In a conventional encapsulated integrated circuit (IC) product, the lead frame (70) is hollow and the lead (71) on top of the lead frame (70) is a continuous wire, as shown in FIG. 1. The lead (71) has to be continuous so as to support each other in the manufacture process. The lead frame (70) has to undergo a trimming process and a forming process to cut off and bend the lead (71) to avoid interference between each semi-product. The two processes prolong the entire manufacture process and thus the manufacture efficiency is low. Although the QFN (Quad Flat Non-Leaded) product amount has increased in popularity in recent years, the same problem bothers the QFN production line.
The application in encapsulated IC products of continuous lead or lead frame still suffers from the following problems:
When the QFN is encapsulated, an adhesive tape is applied to the bottom of the lead frame to prevent overflow of the molding compound or encapsulation material. However, the molding compound or encapsulation material may flow to the bottom of the lead frame and the contacts on the bottom of the lead frame are contaminated. A different method is to use a stop attached to the bottom of the lead frame to prevent the encapsulation material from overflow. After the encapsulation process is finished, the stop is then removed. Although either method effectively stops encapsulation material overflow, however, manufacture cost is increased and product quality is decreased.
Furthermore, during the trimming process, due to the continuity of the lead, the blade is constantly engaged in the cutting process and so is worn out quickly, whereby the manufacture cost is high.
Tests for conductivity of the IC product have to wait until after the completion of the trimming process and thus the overall manufacture processing time is prolonged.
To overcome the shortcomings, the present invention tends to provide an improved encapsulated IC product to mitigate the aforementioned problems.